U.S. Senator Claire McCaskill. (Rachel Lippmann, St. Louis Public Radio)

Missouri Senator Claire McCaskill is calling President Obama's budget a starting point to begin the conversation between Democrats and Republicans.

The Democratic senator says she is anxious to see the Republicans' budget plan in the House. But McCaskill is also criticizing the GOP for focusing on the discretionary domestic budget, which, she says, is only 18 percent of the budget.

"Obviously, we have to get to this ridiculous notion that we can afford to write checks to very wealthy corporations and individuals in this country, McCaskill said, "I'm not talking about raising their taxes. I'm talking about subsidies we give very wealthy corporations."

McCaskill says a good place to start would be to reduce contracting at the Pentagon, which she says is not competitive and more expensive than it needs to be.